Software-defined networking (SDN) with flexible grid optical networks is expected to considerably enhance the capacity and fluidity of optical communications. In a typical configuration, coherent receivers are followed by adaptive digital signal processing designed to mitigate impairments and demodulate the received data. But, these architectures generally require critical transmitter and/or channel information be available at the receiver. For example, to function effectively, such architectures depend on the receiver having maximum foreknowledge of a received signal's transmission parameters such as modulation format, symbol rate (i.e., baud rate or modulation rate), and carrier frequency, as well as the number of the multiplexed polarizations and the length of the signal's transmission over fiber and the type of fiber used in the transmission. In many circumstances, however, such foreknowledge is unavailable. Further, because of growing diversity in optical network transportation standards, numerous incompatibilities exist between transceivers, further limiting transceiver flexibility and complicating the process of transmitting and receiving optical signals. Accordingly, a need exists for a receiver that is capable of identifying and decoding a signal without any or all of the typically-required foreknowledge of the signal's parameters.